ABSTRACT
Advanced Rider Assistance Systems (ARAS) are solutions developed to reduce the crashes rate of Powered Two Wheelers (PTWs). They assist riders in their driving task by transmitting information on their environment or by automatically controlling the dynamics of their vehicle. This study describes a methodology for evaluating the impact of 14 ARAS on PTWs crashes. This methodology consists first of establishing links between ARAS functionalities and riders' failures in crashes situations. Then, an analysis of real crashes cases was conducted using two reals crashes databases: the "In-depth crashes investigation at the Laboratory of Accident Mechanisms Analysis (LMA)" in Salon-de-Provence, France, and the "Initiative for the Global harmonization of Accidents Data". A total of 390 crashes were analyzed. The results showed that ARAS had an influence on 61.5% of the crashes studied. ARAS benefits at the French national level were also assessed, with a weighting of the results obtained. In the French national data, the Anti-lock Braking System had the highest overall impact among the ARASs, estimated to have influenced 39.1% of crashes. Next, emergency braking systems influenced 30.1% of crashes, and an anti-collision warning system had an impact on 29.8% of crashes. This work provided an initial assessment of the most promising technologies for PTWs road safety. It could be used to guide industry and road safety policy towards the development of the most beneficial systems, and the introduction of standards or regulations.
ABSTRACT
The paper presents an experimental study conducted to evaluate the feasibility of using accelerometers as an indirect means to estimate water depths on road surfaces. It makes use of the vibration of the vehicle's wheel arch due to water droplets projected by a tire rolling on a wet road surface. A trailer equipped with a wheel and towed by a van was used. The test setups to spread water on the road surface and before the test wheel, measure the water depth and visualize the water spray are described. The test program, conducted on a test track closed to the traffic, includes three surfaces and two speeds. Visualization of water flows by means of high-speed cameras makes it possible to choose a suitable location for the accelerometers. It turns out that signals provided by the accelerometers are affected by the trailer's movement; a filtering method has been successfully developed to remove noises. Results show a tight relationship between the mean amplitude of accelerometric signals and actual water depths. Discussions are made in terms of effects of the vehicle speed and the road surface texture. Perspectives for using the developed system to improve passenger safety under autonomous driving conditions are presented.
